Collapsible container

ABSTRACT

A collapsible container having a base or bottom wall and having an open border frame defining the top. Foldable side walls are hinged to the base and to the border frame, and end walls are hinged to the border frame only. When the container is collapsed, the side walls fold inwardly and the end walls swing up and inward into the plane of the border frame.

g United States Patent 91 [111 3,870,185

Sanders et al. Mar. 11, 1975 [5 COLLAPSIBLE CONTAINER 3,796,342 3/1974 Sanders et al. 220/6 [75] Inventors: Ellsworth E. Sanders, Sanibel S 75 Elsmer Kreeger Primary ExaminerWilliam 1. Price Ontlac Assistant Examiner-Steven M. Pollard [73] Assignee: llinckqey Mq lqgd P lastigg lnc Attorney, Agent, or Firm-Whittemore, l-lulbert &

Pinckney, Mich. Belknap [22] Filed: Oct. 29, 1973 21 A l. N 410 374 1 pp 0 [57 ABSTRACT Related U.S. Application Data [63] Continuatiomin-pafi of Ser. No 59,8 J e 5, A collapsible container having a base or bottom wall 1972, Pat 1 3 and having an open border frame defining the top. Foldable side walls are hinged to the base and to the [52] U.S. Cl. 220/6, 220/15 border frame, and end walls are hinged to the border [5 Int. Cl. frame nly when the ontainer is ollapsed the Side of Search 7, wall inwardly and the end walls wing up and inward into the plane of the border frame. [5 6] References Cited UNITED STATES PATENTS 8 Claims, 13 Drawing Figures 2,868,407 1/1959 Woodcock 220/7 w, //z I m a f /0 i 9 i 1 l I -.-F' if 1F" 1-1-3- i '7 1 LDDDDDDDDEDDDDD J ED DDDDDDDDDDD LUDDDDDDDDDD DDDDDDDDDDDEH [DDDDDD l H" DDDD plnfifi mmmwmggmmmmmggwmmmg 7 g lij 2:2: 5;

PATENTEUNARI 1 1975 I 3.870185 SHEET 1 BF 5 I A; FIG-a 32 Z ATENTEB NARI I I9? SHEET 2 OF 5 L mwrlrllwl lll .I. .Il l LEII I II II .III LEI PATENTEB MAR] 1 I975 sum 3 of 5 COLLAPSIBLE CONTAINER REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of our copending application Ser. No. 259,844 filed June 5, 1972, now US. Pat. No. 3,796,342. A similar although specifically different container was disclosed in the application of Ellsworth E. Sanders, Ser. No. 422,931, filed Jan. 4, 1965, and now abandoned.

SUMMARY OF THE INVENTION The container of this invention may be made of any suitable material, preferably plastic. When upright, the walls of the container are vertical and provide a maximum of interior space for packing. When collapsed, the container is reduced to a fraction of its normal height so that it takes up very little space. The container also has the advantage when collapsed of stacking with other collapsed containers.

The container is molded in separate parts, one part consisting of the base or bottom wall. The side walls each consists of two separately molded parts. The top border frame of the container comprises another part to which the side walls are connected by locking bars which comprise additional parts of the assembly. Each end wall is a separately molded part. The various separately molded parts of the container readily snap together in a permanent assembly. The novel snap connections joining the parts constitute important features of the invention.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings illustrating a preferred embodiment of the invention wherein:

FIG. 1 is a top plan view of a container embodying our invention.

FIG. 2 is an enlarged fragmentary view with parts in section of a portion of FIG. 1 taken on the line 22 in FIG. 7.

FIG. 3 is a side elevational view of the container shown in FIG. 1.

FIG. 4 is a fragmentary perspectiveview with parts in section of a portion of the base.

FIG. 5 is a fragmentary sectional view of the container in collapsed position, the phantom lines illustrating a second container in stacked relation thereon.

FIG. 6 is an end elevational view of the container with parks in section and parts broken away.

FIG. 7 is an enlarged side elevational view of one end portion of the container with parts in section.

FIG. 8 is an exploded view in'perspective with parts in section showing a portion of a side rail of the border frame and a portion of one of the locking bars.

FIG. 9 is a fragmentary perspective view partly in section showing an upper portion of one of the side wall parts.

FIG. 10 is a fragmentary sectional view taken on the line l0--l0 in FIG. 3.

FIG. 11 is similar to FIG. 10 but shows the container collapsed, and in phantom lines shows the container partially collapsed.

FIG. 12 is a fragmentary detail view of a portion of a locking bar.

FIG. 13 is a fragmentary detail view of a portion of a side rail of the border frame.

Referring now more particularly to the drawings, the container is shown as being an open top container, although it may be provided with a top or lid, if desired. The container is generally designated 10 and, as indicated above, may be collapsed from its normal position of use shown in FIGS. 3, 6, 7 and 10 to a flat compact position shown in FIGS. 5 and 11. FIG. 11 illustrates the container in an intermediate stage between fully erect and collapsed positions in phantom lines. The container when erect or upright may be used to carry any desired material although it is particularly designed as a container for'egg cartons. The container may be made of any suitable material preferably plastic, such for example as molded polyethylene or polypropylene. Such materials are strong yet sufficiently flexible tov permit the snap connections described hereinafter. The container consists of separately molded or formed parts which are readily joined together by snap connections but which when put together provide a virtually perm anent assembly. It is not intended that the container should be taken apart once assembled. The container can of course be disassembled although with some difficulty and usually with the aid of a tool suitable for the purpose.

The container parts include a base or bottom wall 12, a top open border frame 15, two separately molded end walls 16, two side walls 18 each composed of separately molded sections or parts 17 and I9, and separately molded side and end locking bars 21 and 23 for connecting the side and end walls to the border frame 15. These separately formed parts are secured together by snap connections hereinafter more fully described to form a permanent assembly which should never need to be disassembled and which in fact'can be disassembled only with considerable effort.

The base or bottom wall 12 as stated is preferably separately formed of molded plastic and in the preferred embodiment is made rectangular in form having the upturned generally vertical peripheral wall 22. Substantially the entire surface of the base'within the peripheral wall, with the exception of a peripheral horizontal ledge 24 joined to the peripheral wall, is preferably of an open grid construction to facilitate cleaning and generally for sanitary. purposes as well as to reduce weight. A plurality of longitudinally spaced horizontal hinge pins 26 which extend lengthwise of the container are mounted on the ledge 24 of the base 12 along each side of the container in aligned relation to each other, being mounted on the ledge 24 by the legs 28. Such pins 26 and legs 28 are integrally molded with the base. These hinge pins 26 are parts of the snap connections employed to join the side walls to the base as will become apparent from the following description. The base has integrally molded legs 30 extending downward from the four corners of the open grid portion of the base to support the container.

The top open border frame 15 of the container is a separately molded part as previously stated. It is rectangular in form and is composed of the side rails 32 and end rails 34 integrally connected end to end.

The side rails of the top border frame 15 are of the cross section or configuration shown in FIG. 13. They are generally of inverted U-shape having the vertical inner flange 36, the outer flange 38 consisting of the vertical lower portion 40 and the upwardly and inwardly inclined upper portion 42 which is joined to the upper edge of the inner flange 36 by the horizontal top or web portion 44. This top or web portion has a plurality of longitudinally spaced elongated rectangular slots 46 which extend lengthwise of the side rails. Such top or web portions 44 are also relieved or cut down where indicated at 48 across each such slot 46 between the ends thereof. An integral rib 49 extends across the rail from flange 36 to flange portion 42 to strengthen the structure.

The end rails 34 of the top open border frame 15 are of the same cross section or configuration as the side rails except for the fact that the vertical portions 40 of the outer flanges are of somewhat less vertical height. Accordingly, the corresponding parts of the end and side rails have been given the same numbers. The end rails will also be seen having a plurality of longitudinally spaced elongated rectangular slots 46 in the top or web portion 44 extending lengthwise of the rails and of identical configuration with the slots 46 in the side rails. Such top or web portions 44 of the end rails are also relieved or cut down where indicated at 48 across the slots between the ends thereof in the same manner as the side rails.

The separately molded upper parts or sections 17 of the side walls are of identical construction. Each is preferably rectangular and of open grid form as illustrated. The upper side wall parts 17 each has a horizontal frame bar 50 along its upper edge out out where indicated at 52 at spaced points along its length to accommodate a horizontal hinge pin 54 in each such cutout portion. Such hinge pins 54 are molded integrally with the upper side parts 17 and are aligned with one another.

Each side wall part 17 also has a horizontal bottom rail 56 to which are integrally molded a plurality of aligned horizontally disposed hinge knuckles 58. As seen in FIGS. 7, l and 11 each hinge knuckle 58 is an open-ended tubular member of generally cylindrical form but longitudinally slotted at 59 from end to end. The cylindrical inner surface wall 60 of the hinge knuckle from one edge of the slot to the other is slightly greater than 180 in extent. This circular inner surface 60 receives a hinge pin on the lower part of the lower side wall part 19 whose diameter is the same as that of inner surface 60 but greater than the width of slot 59 as more fully described hereinafter. The bottom surface 62 of the rail 56 and the opposed upper surface 64 of the lip 66 of the hinge knuckle 58 diverge to provide a flaring entrance to pilot the hinge pin when pressed into the hinge knuckle. This entrance or pilot is wider than pin 54 at its outer end and narrower than pin 54 at its inner end where it merges into the slot 59. The plastic material of which the hinge knuckle is molded is sufficiently flexible to permit the hinge pin to enter when forced with sufficient pressure.

The bottom parts 19 of the side wall 18 are identical and like the upper parts are of generally rectangular form. Each has an upper rail 70 whichis recessed where indicated at 72 at spaced points along its length to accommodate aligned horizontalhinge pins 74. Each such hinge pin is integrally molded and registers with a hinge knuckle 58 of the upper molded side part 17. Such hinge pins 74 have a diameter the same as the inner surface 60 of the hinge knuckles but greater than the width of slots 59 and are snapped into hinged relationship therewith as seen in FIGS. 7, l0, and 11 by a lateral movement through the slots.

The lower rail of the bottom part 19 of each side wall is formed with a recess 82 to receive or clear one of the hinge pins 26 along a side of the base, and in such recessed portions 82 the lower side wall 19 has integrally molded aligned horizontal hinge knuckles 86 each of which is an open-ended tubular member of generally cylindrical form but longitudinally slotted at 87 from end to end. The cylindrical inner surface 88 of the hinge knuckle from one edge of the slot to the other is slightly greater than 180 in extent. As shown in FIG. 10, leading into the slotted side is a flaring entry way defined by the walls 92 and 94 which is wider at its outer end but narrower at its inner end where it merges with slot 87 than hinge pins 26 to permit the hinge pins 26 to be forced laterally through slots 87 into the hinge knuckles under pressure in the relationship shown in FIGS. 7, l0 and 11. The plastic flexes enough to permit this. Such hinge pins 26 have a diameter the same as the inner surface 88 of the knuckles but greater than the width of slots 87.

Each side locking bar 21 comprises an elongated molded flat strip which has at spaced points along its length a plurality of alignedhorizontal hinge knuckles as seen in FIGS. 7, 10, 11 and 12. Such knuckles 100 are like knuckles 86, being an open-ended tubular member of generally cylindrical form but longitudinally slotted at 101 from end to end. The cylindrical inner surface 102 is of the same diameter as the hinge pins 54 along the tops of the upper side wall parts 17 but the hinge pin diameter is greater than the width of the slots 101. Such inner surfaces 102 are of slightly greater than 180 in extent and the flaring surfaces 104 leading into the slotted side provide a guide or pilot for the entry of the hinge pins 54 when forced laterally under pressure through the slots into the hinge knuckles.

Each locking bar also has on its upper edge a plurality of spaced integrally molded elongated ribs which are of the same length and width and spaced apart the same distance as the slots 46 in the side rails 21 of the open top border frame 15. Each rib 110 has molded intermediate its length a T-shaped head portion 112 formed with laterally outwardly projecting extensions 114. The head portion 112 is of the same length as the recessed'portions 48 extending across the slots 46 in the side rails. To assemble the locking bars with the side rails, they are forced up between the side flanges of the side rails so that the ribs 110 enter the slots 46 and the extensions 114 of head portion 112 overlie the recessed portions 48. There is sufficient flexibility in the flanges of the side walls to allow them to spread and clear the head as it is forced up into position, after which the flanges snap back to their unstressed condition to lock the parts together. The locking bars 21 also are notched as at 111 to clear the ribs 49 of the side rails.

The end locking bars 23 are of the same form and construction as the side locking-bars having the ribs 110, head portions 112 and hinge knuckles 100 as shown in FIG. 12. They are, of course, shorter than the side locking bars. End locking bars 23 snap into the end rails 34 of the top border frame 15 in the same manner as the side locking bars 21 snap into the side rails.

Each end wall 16 has a top rail provided with longitudinally spaced recessed portions 122 in which are disposed integrally molded horizontal, aligned hinge pins 124. The hinge pins 124 are positioned to register with the hinge knuckles 100 on the end locking bars and are of the same diameter as the inside of the hinge knuckles, such diameter being greater however than the width of the slots leading to the knuckles. The pins are snapped laterally through the slots into the knuckles in the same manner as the hinge pins on the top side wall parts 17 are snapped into the hinge knuckles of the side locking bars.

The end walls have intermediate their height along each side vertical edge a rearwardly projecting part or fin 130. The lower portion of each upper side wall part 17 has along each side edge an inwardly extending loop formation 132. Such fins or projections 130 on the end walls are adapted to extend into the loops 132 of the side walls in the upright position of the container. The end walls when upright rest against peripheral wall 22 of base 12 and engage the inner surfaces of the upright side walls along the side edges of the latter to prevent the side walls from collapsing.

The end ledges 24 on the base 12 may have molded detents 140 to retain the end walls in the upright position. Such detents are inclined as indicated at 142 to permit the bottoms of the end walls to cam over the detents when swung to upright position.

In order to collapse the container, an upward and inward manual pressure is applied to the end walls 16 to lift them over the substantially vertical retaining parts 144 of the detents and swing them to a horizontal position about their upper hinges into the plane of the top border frame 15. The side walls 18 are now released so that they may readily fold inwardly to collapse the container to the position of FIGS. 5 and 11. FIG. 5 shows in phantom lines a second collapsed container in stacked relationship with the one shown in section indicating that a plurality of containers when collapsed may be readily stacked one upon another.

In the foregoing description and the appended claims, reference is made to side walls and end walls of the container. The use of the words side and end" is solely for the purpose of distinguishing one set of opposite walls from the other and should not be taken as implying that one set of walls is necessarily longer or shorter than the other.

What we claim as our invention is:

l. A plastic collapsible container comprising a rectangular bottom Wall, two opposed vertical side walls, two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side Walls each having upper and lower wall sections, said border frame, upper and lower side wall sections, said end walls and said bottom wall being separately formed, means providing snap hinge connections between the adjacent edges of said upper and lower wall sections, means providing snap hinge connections between the upper edges of said upper wall sections and said border frame and means providing snap hinge connections between the lower'edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing snap hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed.

2. The container defined in claim 1, wherein each hinge connection comprises a hinge knuckle in the form of an elongated open ended tubular member of generally cylindrical form but longitudinally slotted from end to end, the inner surface of said tubular member being cylindrical and more than in arcuate extent from one edge of the slot to the other, and a hinge pin of a diameter greater than the width of said slot received in said hinge knuckle and being insertable laterally therein through said slot, said tubular member being formed of a sufficiently flexible plastic to yield when said pin is inserted therein as aforesaid.

3. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls, two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, said border frame, said upper and lower side wall sections, said end walls and said bottom wall being separately formed, means providing hinge connections between the adjacent edges of said upper and lower wall sections, means providing hinge connections between the upper edges of saidupper wall sections and said border frame and means providing hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed, said border frame being of inverted U shape in cross section having inner and outer flanges connected at the top by a web, said means providing said hinge connections between said border frame and each end wall and between said border frame and said upper edge of each upper side wall section comprising an elongated locking bar, an elongated slot in the web of said border frame, said locking bar having along its upper edge a locking part of generally T-shape consisting of an upstanding rib of no greater length than said slot and a head at the top of greater width than said slot, the rib of said locking part projecting into said slot with said head overlying said slot to prevent withdrawal of said locking bar, said locking part being insertable into said slot by being pressed upwardly between the flanges of said border frame, said border frame being of sufficiently flexible plastic material to admit said locking part into said slot during assembly and to snap into locked relationship therewith after assembly.

4. The container defined in claim 3, wherein said rib and slot are of greater length than said head so that said slot may have sufficient flexibility to clear said head during insertion of said locking part as aforesaid.

5. The container defined in claim 3, wherein each hinge connection comprises a hinge knuckle in the form of an elongated open ended tubular member of generally cylindrical form but longitudinally slotted from end to end, the inner surface of said tubular member being more than 180 in arcuate extent from one edge of the slot to the other, and a hinge pin of a diameter greater than the width of said slot received in said hinge knuckle and being insertable laterally therein through said slot, said tubular member being formed of a sufficiently flexible plastic to yield when said pin is inserted therein as aforesaid.

6. The container defined in claim 5, including pilot means for guiding said pin through said slot during insertion thereof into said hinge knuckle.

7. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls,

two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, means providing hinge connections between the adjacent edges of said upper and lower wall sections, means providing hinge connections between the upper edges of said upper wall sections and said border frame and means providing hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed, one of said hinge connections comprising a hinge knuckle in the form of an elongated open ended tubular member of generally cylindrical form but longitudinally slotted from end to end, the inner surface of said tubular member being cylindrical and more than 180 in arcuate extent from one edge of the slot to the other, and a hinge pin of a diameter greater than the width of said slot received in said hinge knuckle and being insertable laterally therein through said slot, said tubular member being formed of a sufficiently flexible plastic to yield when said pin is inserted therein as aforesaid.

8. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls,-

two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, means providing hinge connections between the adjacent edges of said upper and lower wall sections, means providing hinge connections between the upper edges of said upper wall sections and said border frame and means providing hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed, said border frame being of inverted U shape in cross section having inner and outer flanges connected at the top by a web, said means providing said hinge connection between said border frame and at least one of said end walls and upper side wall sections comprising an elongated locking bar, an elongated slot in the web of said border frame, said locking bar having along its upper edge a locking part of generally T shape consisting of an upstanding rib of no greater length than said slot and a head at the top of greater width than said slot, the rib of said locking part projecting into said slot with said head overlying said slot to prevent withdrawal of said locking bar, said locking part being insertable into said slot by being pressed upwardly between the flanges of said border frame, said border frame being of sufficiently flexible plastic material to admit said locking part into said slot during assembly and to snap into locked relationship therewith after assembly. 

1. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls, two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, said border frame, upper and lower side wall sections, said end walls and said bottom wall being separately formed, means providing snap hinge connections between the adjacent edges of said upper and lower wall sections, means providing snap hinge connections between the upper edges of said upper wall sections and said border frame and means providing snap hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing snap hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed.
 1. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls, two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, said border frame, upper and lower side wall sections, said end walls and said bottom wall being separately formed, means providing snap hinge connections between the adjacent edges of said upper and lower wall sections, means providing snap hinge connections between the upper edges of said upper wall sections and said border frame and means providing snap hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing snap hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed.
 2. The container defined in claim 1, wherein each hinge connection comprises a hinge knuckle in the form of an elongated open ended tubular member of generally cylindrical form but longitudinally slotted from end to end, the inner surface of said tubular member being cylindrical and more than 180* in arcuate extent from one edge of the slot to the other, and a hinge pin of a diameter greater than the width of said slot received in said hinge knuckle and being insertable laterally therein through said slot, said tubular member being formed of a sufficiently flexible plastic to yield when said pin is inserted therein as aforesaid.
 3. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls, two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, said border frame, said upper and lower side wall sections, said end walls and said bottom wall being separately formed, means providing hinge connections between the adjacent edges of said upper and lower wall sections, means providing hinge connections between the upper edges of said upper wall sections and said border frame and means providing hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed, said border frame being of inverted U shape in cross section having inner and outer flanges connected at the top by a web, said means providing said hinge connections between said border frame and each end wall and between said border frame and said upper edge of each upper side wall section comprising an elongated locking bar, an elongated slot in the web of said border frame, said locking bar having along its upper edge a locking part of generally T-shape consisting of an upstanding rib of no greater length than said slot and a head at the top of greater width than said slot, the rib of said locking part projecting into said slot with said head overlying said slot to prevent withdrawal of said locking bar, said locking part being insertable into said slot by being pressed upwardly between the flanges of said border frame, said border frame being of sufficiently flexible plastic material to admit said locking part into said slot during assembly and to snap into locked relationship therewith after assembly.
 4. The container defined in claim 3, wherein said rib and slot are of greater length than said head so that said slot may have sufficient flexibility to clear said head during insertion of said locking part as aforesaid.
 5. The container defined in claim 3, wherein each hinge connection comprises a hinge knuckle in the form of an elongated open ended tubular member of generally cylindrical form but longitudinally slotted from end to end, the inner surface of said tubular member being more than 180* in arcuate extent from one edge of the slot to the other, and a hinge pin of a diameter greater than the width of said slot received in said hinge knuckle and being insertable laterally therein through said slot, said tubular member being formed of a sufficiently flexible plastic to yield when said pin is inserted therein as aforesaid.
 6. The container defined in claim 5, including pilot means for guiding said pin through said slot during insertion thereof into said hinge knuckle.
 7. A plastic collapsible container comprising a rectangular bottom wall, two opposed vertical side walls, two opposed vertical end walls, a top rectangular border frame defining the top of the container, said side walls each having upper and lower wall sections, means providing hinge connections between the adjacent edges of said upper and lower wall sections, means providing hinge connections between the upper edges of said upper wall sections and said border frame and means providing hinge connections between the lower edges of said lower wall sections and said bottom wall to permit inward folding of said side walls when said container is collapsed, and means providing hinge connections between the upper edges of said end walls and said border frame to permit inward swinging of said end walls to a substantially horizontal position when said container is collapsed, one of said hinge connections comprising a hinge knuckle in the form of an elongated open ended tubular member of generally cylindrical form but longitudinally slotted from end to end, the inner surface of said tubular member being cylindrical and more than 180* in arcuate extent from one edge of the slot to the other, and a hinge pin of a diameter greater than the width of said slot received in said hinge knuckle and being insertable laterally therein through said slot, said tubular member being formed of a sufficiently flexible plastic to yield when said pin is inserted therein as aforesaid. 